What Is Power-over-Ethernet (PoE) Switch?
A Power-over-Ethernet (PoE) Switch is a device that provides not only network connectivity but also power to connected devices.
Power-over-Ethernet (POE) refers to a technology that provides power through a network cable (typically a Category 5 or higher Ethernet cable). POE switches allow for the installation of devices in hard-to-power locations or devices that do not want to run power cables.
The benefits of Power-over-Ethernet (PoE) Switch are significant, reducing the need for power wiring, increasing installation flexibility, and increasing power availability. This makes them ideal for use in business environments and large network infrastructures.
Uses of Power-over-Ethernet (PoE) Switches
Power-over-Ethernet (PoE) Switches are used in conjunction with PoE-enabled devices such as IP phones, wireless access points, and network cameras. They are especially beneficial in environments where cabling is a constraint.
1. Deploying IP Phones in an Office
When installing multiple IP phones in an office, the combination of a PoE switch and IP phones eliminates the need for power wiring for each phone.
2. Wireless Access Point Installation in Hotels and Office Buildings
When providing a wireless environment over a large area, a flexible network design is possible with PoE switches and access points.
3. Installation of Surveillance Cameras in Stores and Factories
By utilizing PoE switches and network cameras, wiring costs and installation man-hours can be significantly reduced.
4. IoT Devices
IoT devices require constant power and network connectivity. Therefore, Power-over-Ethernet (PoE) Switches can play a central role in smart buildings and automation systems.
Principle of the Power-over-Ethernet (PoE) Switch
An Ethernet cable has eight signal lines, four of which are used for data transmission and the other four for DC power supply. Power-over-Ethernet (PoE) Switch superimposes DC voltage on the signal lines for power supply in addition to the signal lines for transmission and reception at the ports where power is supplied.
Power-over-Ethernet (PoE) Switches and terminals are connected to each other in accordance with standards such as IEEE802.3af/at/bt, which standardize specifications such as power supply, superposition method, and device detection and control. Compliance with these standards ensures interoperability.
Thus, Power-over-Ethernet (PoE) Switch can supply data and power simultaneously over a single LAN cable, reducing wiring and installation man-hours. It is a technology that increases the flexibility of network equipment deployment.
Types of Power-over-Ethernet (PoE) Switches
Power-over-Ethernet (PoE) Switch is a type of network switch that has the ability to supply power to specific devices. Depending on the method, there are two main types of PoE switches: active PoE and passive PoE.
1. Active Power-over-Ethernet (PoE) Switch
Active PoE automatically detects whether a device supports PoE and provides power only if it does. This type of PoE complies with the IEEE 802.3af/at standard and automatically adjusts the power required by the device.
Active Power-over-Ethernet (PoE+ standard) Switches can provide up to 30W (for PoE+ standard) and are widely used as general switches.
2. Passive Power-over-Ethernet (PoE) Switch
Passive PoE has no automatic equipment detection or power regulation. Passive Power-over-Ethernet Switches always supply a specific voltage (typically 24V or 48V). It is recommended that this be used only for supported devices. Powering an unsupported device may damage the device.
These two are used to address different situations and needs. Active PoE supports a variety of PoE-enabled devices and automatically manages the power supply, making it suitable when more flexibility and safety are required.
Passive PoE, on the other hand, is used to provide low-cost, efficient power delivery for a specific configuration or device. However, it is important to check the compatibility of the devices used beforehand.